/*
 *      ID : pallab81
 *      PROG : 11432
 *      LANG : C++
 *
 *      2012-06-11 19:20:30
 *      "I have not failed, I have just found 10000 ways that won't work.
 */

#include <iostream>
#include <algorithm>
#include <vector>
#include <sstream>
#include <fstream>
#include <string>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <stack>
#include <functional>
#include <bitset>
#include <iomanip>

#include <ctime>
#include <cassert>
#include <cstdio>
#include <cmath>
#include <cstring>
#include <climits>
#include <cstdlib>

using namespace std;


#define foR(i1,st,ed) for(int i1 = st , j1 = ed ; i1 < j1 ; ++i1 )
#define fo(i1,ed) foR( i1 , 0 , ed )
#define foE(i1,st,ed) foR( i1, st, ed+1 )
#define foit(i, x) for (typeof((x).begin()) i = (x).begin(); i != (x).end(); i++)
#define bip system("pause")
#define Int long long
#define pb push_back
#define SZ(X) (int)(X).size()
#define LN(X) (int)(X).length()
#define mk make_pair
#define SET( ARRAY , VALUE ) memset( ARRAY , VALUE , sizeof(ARRAY) )
#define line putchar_unlocked('\n')

template<class T1>
inline void debug(T1 _x) {
    cout<<_x<<'\n';
}
template<class T1, class T2>
inline void debug(T1 _x,T2 _y) {
    cout<<_x<<' '<<_y<<'\n';
}
template<class T1, class T2, class T3>
inline void debug(T1 _x,T2 _y,T3 _z) {
    cout<<_x<<' '<<_y<<' '<<_z<<'\n';
}
template<class T1, class T2, class T3, class T4>
inline void debug(T1 _x,T2 _y,T3 _z,T4 _zz) {
    cout<<_x<<' '<<_y<<' '<<_z<<' '<<_zz<<'\n';
}
template< class T1>
inline void debug(T1 _array,int _size) {
    cout<<"[";
    for (int i=0; i<_size; ++i) {
        cout<<' '<<_array[i];
    }
    puts(" ]");
}

#define getchar getchar_unlocked
#define putchar putchar_unlocked

inline void fastRead(int *a) {
    register char c=0;
    while (c<33) c=getchar();
    *a=0;
    while (c>33)
    {
        *a=*a*10+c-'0';
        c=getchar();
    }
}
inline string fastRead() {
    register char c[33];
    gets(c);
    return (string)c;
}
inline bool CI(int &_x) {
    return scanf("%d",&_x)==1;
}
inline bool CI(int &_x, int &_y) {
    return CI(_x)&&CI(_y) ;
}
inline bool CI(int &_x, int &_y, int &_z) {
    return CI(_x)&&CI(_y)&&CI(_z) ;
}
inline bool CI(int &_x, int &_y, int &_z, int &_zz) {
    return CI(_x)&&CI(_y)&&CI(_z)&&CI(_zz) ;
}
inline void wait( double seconds ) {
    double endtime = clock()+( seconds* CLOCKS_PER_SEC );
    while ( clock() < endtime ) {
        ;
    }
}
int D,G;
const int mxn=35;
Int dp[mxn][mxn][mxn][mxn][2];


Int go(int a, int b, int ac, int bc,int taken, int prv,int atg) {
    Int &nways = dp[atg][a][b][taken][prv];
    if (nways!=-1)return nways;
    nways=0LL;

    if (a==0) {
        return nways=1LL;
    }
    if (b==0) {
        return nways=0LL;
    }


    if (prv==0) {
        //b continue korbo
        for (int nb=b, nbc=bc; ;) {
            --nb;
            ++nbc;
            if (nbc>G||nb<0)break;
            nways+=go(a,nb,0,nbc,nbc,1,atg);
        }
    }
    else {
        //a continue korbo
        for (int na=a,nac=ac; ;) {
            --na;
            ++nac;
            if (nac>G||na<0)break;
            nways+=go(na,b,nac,0,nac,0,atg);
        }
    }

    return nways;
}

inline void Solve() {
    //SET(dp,-1);
    G=min(D,G);
    Int v = go(D,D,0,0,0,1,G);
    cout<<(v<<1);
    line;
}

#define showcase
int main() {
    SET(dp,-1);
    int kase=1;
    while ( scanf("%d %d",&D,&G)==2 ) {
        if ( D==-1&&G==-1)break;
#ifdef showcase
        cout<<"Case "<<kase<<": ";
#endif
        Solve();
        ++kase;
    }


    return 0;
}
// kate: indent-mode cstyle; space-indent on; indent-width 0;